ABSTRACT
This chapter discusses several aspects of automated leukocyte differential analyzers, including some history of their development, what they do, how they work, and how to evaluate their performance. It describes the leukocyte (white blood cell) differential count as it is performed in a clinical laboratory. The chapter provides an overview of the development of automated analyzers from a historic view and briefly discusses the major attributes of histochemical and pattern recognition machines. It deals more directly with the hardware required to implement an automated analyzer. The chapter explores how some computerized image processing techniques can be used to extract the attributes of a leukocyte from a visual image. It also provides some insight into the techniques used in processing visual images with a computer. The chapter also deals with the topics of automated sample preparation and the desirability of producing samples of uniform quality. It explores some recommended techniques for evaluating the performance of an automated analyzer.
